Should athletes be screened for heart problems?

The collapse of footballer Fabrice Muamba on live television on 17 March has sparked a debate about how often athletes should be screened for heart abnormalities. Could regular screening prevent sudden cardiac arrests?

What happened to Fabrice Muamba?The Bolton Wanderers player collapsed on the pitch, and his heart stopped, although it is not clear why. Reports suggest Muamba's heart stopped beating for two hours, but paramedics kept blood flowing to his brain through cardiac compression. Heart problems usually occur either because a blood clot blocks the coronary artery supplying the heart, or because of rhythmic or electrical disturbances to the heart muscles. No explanation has yet been given on why the footballer's heart stopped working.

What's the latest on his condition?According to an official statement from doctors and the football club, Muamba can now breathe on his own, has movement in his arms and legs, can recognise family members and responds appropriately to questions.

Could regular screening catch such heart problems?Some football managers, including Roberto Mancini of Manchester City, called this week for players to be screened twice a year to intercept potential heart problems.

This causes a dilemma, says Sanjay Sharma, a cardiologist at St George's, University of London, because such conditions typically affect only 1 in 50,000. "It means we would have to screen several thousand athletes to identify just one or two at risk," he says.

Has regular screening worked anywhere else?Yes. Italy is the only country where all professional and amateur athletes have been required by law since 1982 to have electrocardiograms (ECG) every year. Research published in 2006 by Domenico Corrado and colleagues at the University of Padua, Italy, revealed that between 1979 and 2004, the death rate plummeted by 89 per cent in screened athletes compared with no change in the general population. "Italy's death rates are the lowest in the world," says Sharma.

Does the UK currently screen athletes?In the UK, screening for athletes has expanded since a charity, Cardiac Risk in the Young, was set up in 1996. Now, screening programmes are run by sporting professional bodies such as the Rugby Football Union and the Lawn Tennis Association. Young footballers who join the Football Association's national academy are also screened for heart problems at the age of 16. However, although most Premiership football clubs screen players privately, there is no compulsory testing or guidance on how frequently it should be done. Sharma believes that all professional footballers, including those outside the premiership, should be screened at least once every two years.

Why were Muamba's heart problems not caught by screening?Muamba has reportedly been screened four times, most recently last August. "No screening programme is fool proof, but the aim is to identify the vast majority at risk. An ECG picks up around 60 to 70 per cent of cases," says Sharma.

Data from Italy suggests that scans wrongly diagnose around 7 per cent of people as having a problem when they don't. Data gathered by Sharma from UK athletes suggests that scans also miss about 3 per cent of those who actually are at risk. He estimates that, overall, only 20 per cent of people with heart abnormalities are identified in the UK. Twelve people under the age of 35 die a week from sudden cardiac death in this country.

What abnormalities actually cause sudden cardiac death?The most common one, accounting for about 35 per cent of cases, is hypertrophic cardiomyopathy, where the cells in the heart muscle are abnormally large causing irregular beating. There are also conditions that produce electrical faults in heart functioning, including long Q-T syndrome and Brugada syndrome, as well as faults in the supply of blood to the heart. Some of these defects are inherited and others are congenital, from faults in body development. Sharma says that the best clues are from family history of sudden death and suspicious symptoms, but in many cases, the first time those affected find out is through a cardiac arrest, just as with Muamba.

Does sport increase the chance of a sudden arrest if you have an abnormality?Sharma says exercise trebles the chance of dying compared with non-athletes with an abnormality. Also, black Afro-Caribbean athletes like Muamba are four times more prone to the abnormalities than other ethnic groups, so they could benefit from extra screening.

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Fabrice Muamba was screened last August(Image: Back Page Images/Rex Features)